Swim-in-place apparatus and methods

ABSTRACT

Apparatus and methods for generating a current used during swim-in-place exercise. Current-generating apparatus can comprise a discharge device having at least 20 spaced-apart, fluid discharge openings comprising a plurality of perimeter openings, where the area defined by the perimeter openings is in the range of from about 0.5 to about 20 square feet.

BACKGROUND OF THE INVENTION

1. Field of the Invention

One or more embodiments of the present invention relate to apparatus and methods for creating a current in a water-containing vessel used during swim-in-place exercise.

2. Description of Related Art

Equipment enabling a user to swim in place can be placed into two main categories. First, a user can be restrained or “tethered” in place in a pool or spa. Second, a device can be employed to create an adjustable current in a pool or spa, allowing a user to swim unrestrained against the current while remaining in relatively the same place. In this latter type of swim-in-place apparatus, the force for the current can be generated by various mechanical devices, such as jets, propellers, pumps, or paddle wheels.

Current-generating swim-in-place apparatus typically come in two varieties: integrated and non-integrated. Integrated devices are those that are constructed along with the pool or spa, and are intended to be permanent fixtures. However, these integrated swim-in-place pools or spas are quite costly. On the other hand, non-integrated systems are available for after-market modification of existing pools or spas that are considerably less expensive than integrated varieties, though the quality of current generated by non-integrated systems can sometimes be lower than that generated by integrated systems. Despite advances in both types of current-generating systems, improvements are still needed.

SUMMARY OF THE INVENTION

One embodiment of the present invention concerns an apparatus for creating a current in a water-containing vessel for use during swim-in-place exercise. The apparatus of this embodiment comprises at least one discharge device configured to receive water from the water-containing vessel and to discharge at least a portion of the water back into the water-containing vessel. The discharge device comprises at least 20 spaced-apart, fluid discharge openings, where the fluid discharge openings comprise a plurality of perimeter discharge openings and the area defined by the perimeter discharge openings is in the range of from about 0.5 to about 20 square feet.

Another embodiment of the present invention concerns an apparatus for creating a current in a water-containing vessel for use during swim-in-place exercise. The apparatus of this embodiment comprises (a) at least one pump; (b) at least one fluid inlet configured to receive water from the water-containing vessel and route at least a portion of the water to the pump; and (c) at least one discharge device configured to receive water from the pump and discharge at least a portion of the water into said water-containing vessel. The discharge device comprises at least 3 distinct fluid discharge conduits each comprising a plurality of spaced-apart, fluid discharge openings. Additionally, the discharge device comprises at least one feeding conduit in fluid communication with all of the fluid discharge conduits and the pump, and the discharge device comprises at least 30 of the fluid discharge openings.

Yet another embodiment of the present invention concerns a method for generating a current in a swim-in-place vessel. The method of this embodiment comprises circulating water contained in the vessel through a current-generating device comprising at least 20 spaced-apart, fluid discharge openings having an average diameter of less than ⅜ of an inch.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Embodiments of the present invention are described herein with reference to the following drawing figures wherein:

FIG. 1 is a schematic view of a current-generating device employed in a water-containing vessel;

FIG. 2 is a front view of a discharge device, particularly illustrating a feeding conduit, a number of fluid discharge conduits, a number of fluid discharge openings, and an area defined by perimeter openings;

FIG. 3 is a top view of the discharge device depicted in FIG. 2;

FIG. 4 is a side view of the discharge device depicted in FIG. 2, particularly illustrating fluid discharge conduits arranged in an alternating, staggered pattern;

FIG. 5 is a front view of an alternate discharge device, particularly illustrating two feeding conduits, a number of fluid discharge conduits, a number of fluid discharge openings, and an area defined by perimeter openings;

FIG. 6 is a front view of an alternate discharge device, particularly illustrating a feeding conduit, a number of fluid discharge conduits, a number of fluid discharge openings, and an area defined by perimeter openings;

FIG. 7 is a front view of an alternate discharge device, particularly illustrating a number of fluid discharge openings and an area defined by perimeter openings; and

FIG. 8 is a schematic view of an alternate discharge device, particularly illustrating a number of fluid discharge openings and an area defined by perimeter openings.

DETAILED DESCRIPTION

Referring initially to FIG. 1, a current-generating apparatus 12 is depicted as including a discharge device 10, a fluid inlet 14, and a plump 16. The current-generating apparatus 12 is shown coupled to a water-containing vessel 18, and generating a current 20 in water 22. Discharge device 10 can be configured to receive water from pump 16, which in turn is configured to receive water from water-containing vessel 18 via fluid inlet 14. At least a portion of the water received by discharge device 10 can be discharged back into water-containing vessel 18 thereby creating current 20. Current 20 generated by current-generating device 12 can be employed during swim-in-place exercise.

As will be discussed with reference to exemplary embodiments below, discharge device 10 can have a variety of configurations. However, all of these configurations present an array of spaced-apart, fluid discharge openings configured to discharge water received by discharge device 10 from pump 16. The properties and arrangement of the fluid discharge openings of discharge device 10 will now be described in general.

Initially, the number and size of the fluid discharge openings can be any sufficient to create current 20 in water 22. In one or more embodiments, discharge device 10 can comprise at least 20, at least 30, at least 40, or at least 50 fluid discharge openings. In one or more embodiments, discharge device 10 can comprise a number of fluid discharge openings in the range of from about 20 to about 500, in the range of from about 30 to about 350, or in the range of from 50 to 100.

Discharge device 10 can comprise a plurality of perimeter discharge openings. As used herein, the term “perimeter discharge openings” shall denote those fluid discharge openings outlying furthest from the centroid of all fluid discharge openings, where such outlying openings are selected in a manner as to define a polygon having the greatest possible area when forming a perimeter by circuitously connecting such selected outlying openings. Additionally, when the fluid discharge openings lie in more than one plane, the perimeter openings shall be defined as those fluid discharge openings outlying furthest from the centroid of all fluid discharge openings, where such outlying openings are selected in a manner that, when theoretically projected in the overall direction of discharge onto a common plane orthogonal to the overall direction of discharge, defines a polygon on the common plane having the greatest possible area when forming a perimeter by circuitously connecting such theoretically projected openings. As used herein, the term “overall direction of discharge” shall denote the common direction in which the greatest number of fluid discharge openings are configured to discharge fluid. In one embodiment, all fluid discharge openings can be configured to discharge fluid in substantially the same direction.

The area defined by the perimeter discharge openings (“discharge area”) can be in the range of from about 0.5 to about 20 square feet, in the range of from about 0.75 to about 10 square feet, or in the range of from 1 to 3 square feet. Additionally, the discharge area can have a maximum width in the range of from about 10 to about 60 inches, in the range of from about 15 to about 50 inches, or in the range of from 20 to 40 inches. Furthermore, the discharge area can have a maximum height in the range of from about 4 to about 50 inches, in the range of from about 6 to about 30 inches, or in the range of from 8 to 20 inches.

Individually, the fluid discharge openings can have any shape desired, such as, for example, circular, square, triangular, etc. In one or more embodiments, the fluid discharge openings can be substantially circular. Additionally, the fluid discharge openings can vary in size, and can individually have diameters in the range of from about 1/32 to about ⅜ of an inch, in the range of from about 1/16 to about 5/16 of an inch, or in the range of from ⅛ to ¼ of an inch. Moreover, in one or more embodiments, the fluid discharge openings can have an average diameter of less than ⅜ of an inch, or less than ¼ of an inch. In one or more embodiments, all of the fluid discharge openings can have substantially the same size and shape. Furthermore, in one or more embodiments, the open area defined by each individual opening can be in the range of from about 7.7×10⁻⁴ to about 1.1×10⁻¹ square inches, in the range of from about 3.1×10⁻³ to about 7.7×10⁻² square inches, or in the range of from 1.2×10⁻² to 4.9×10⁻² square inches. Additionally, in one or more embodiments, the total open area defined by all fluid discharge openings in discharge device 10 can be in the range of from about 0.2 to about 6 square inches, in the range of from about 0.4 to about 4 square inches, or in the range of from 0.6 to about 2 square inches.

As mentioned above, the fluid discharge openings can be spaced apart such that the average spacing between adjacent fluid discharge openings is at least 1/16 of an inch, at least ⅛ of an inch, or at least ¼ of an inch, as measured from the outer edge of the fluid discharge openings. Furthermore, the average spacing between adjacent fluid discharge openings can be in the range of from about 1/16 of an inch to about 10 inches, in the range of from about ⅛ of an inch to about 5 inches, or in the range of from ¼ of an inch to 1 inch.

Though not wishing to be bound by theory, it is believed that the use of a greater number of smaller, spaced-apart fluid discharge openings than have heretofore been employed in current-generating devices has a multiplying effect on the discharged fluid, thus creating a stronger, smoother current. This effect may possibly be explained by Bernoulli's principle.

As will be discussed in relation to exemplary embodiments below, discharge device 10 can comprise a plurality of distinct fluid discharge conduits 26. In one or more embodiments, discharge device 10 can comprise at least 3, at least 4, at least 5, or at least 6 of fluid discharge conduits 26. Additionally, each of fluid discharge conduits 26 can comprise a plurality of the above-described fluid discharge openings. In one or more embodiments, each of fluid discharge conduits 26 can comprise at least 3, at least 5, or at least 7 fluid discharge openings. In other embodiments, each of fluid discharge conduits 26 can comprise a number of fluid discharge openings in the range of from about 3 to about 50, in the range of from about 5 to about 35, or in the range of from 7 to 20. In one or more embodiments, fluid discharge conduits 26 can be substantially cylindrical in shape.

Referring now to FIGS. 2-4, fluid discharge device 10 is depicted comprising a feeding conduit 28 and seven fluid discharge conduits 26 positioned on each of two opposing sides of feeding conduit 28. Fluid discharge conduits 26 can extend from feeding conduit 28, such that all of fluid discharge conduits 26 are in fluid communication with feeding conduit 28. Additionally, in one or more embodiments, fluid discharge conduits 26 can be substantially perpendicular to feeding conduit 28. In one or more embodiments, feeding conduit 28 can be positioned substantially vertically.

Feeding conduit 28 can have any shape known in the art. In one or more embodiments, feeding conduit 28 can be substantially cylindrical. In one or more embodiments, feeding conduit 28 can comprise a plurality of preformed discharge conduit couplings 34 configured to be rigidly coupled with fluid discharge conduits 26. Feeding conduit 28 can have a diameter of at least 0.5 inches, at least 1 inch, or at least 1.5 inches. Additionally, feeding conduit 28 can have a diameter in the range of from about 0.5 to about 10 inches, in the range of from about 1 to about 5 inches, or in the range of from 1.5 to 2.5 inches. Furthermore, feeding conduit 28 can have a length in the range of from about 1 to about 40 inches, in the range of from about 3 to about 30 inches, or in the range of from 5 to 20 inches. Also, though not depicted, feeding conduit 28 can optionally comprise a plurality of fluid discharge openings, such as those described above. In one or more embodiments, feeding conduit 28 can comprise at least 3, at least 5, or at least 7 fluid discharge openings. In other embodiments, feeding conduit 28 can comprise a number of fluid discharge openings in the range of from about 3 to about 50, in the range of from about 5 to about 35, or in the range of from 7 to 20.

In one or more embodiments, fluid discharge conduits 26 can be arranged in a substantially horizontal manner, and can be substantially parallel to one another. As perhaps best depicted by FIG. 4, fluid discharge conduits 26 can be arranged in an alternating staggered fashion, such that adjacent fluid discharge conduits 26 lie in different vertical planes. Though not wishing to be bound by theory, it is believed that such staggered placement of fluid discharge conduits 26 has a multiplying effect on the discharged fluid, which may again be possibly explained by Bernoulli's principle. Furthermore, adjacent ones of fluid discharge conduits 26 can be spaced apart at least 0.5 inches on center, at least 1 inch on center, or at least 1.5 inches on center.

Each of fluid discharge conduits 26 can have an individual length of at least 5, at least 7, or at least 10 inches. In one or more embodiments, each of fluid discharge conduits 26 can have an individual length in the range of from about 5 to about 50 inches, in the range of from about 7 to about 40 inches, or in the range of from 10 to 30 inches. In one or more embodiments, fluid discharge conduits 26 can have individual diameters of at least about 0.5 inches, at least 0.75 inches, or at least 1 inch. Additionally, fluid discharge conduits 26 can have individual diameters in the range of from about 0.5 to about 5 inches, in the range of from about 0.75 to about 3 inches, or in the range of from 1 to 2 inches.

As discussed above, discharge device 10 can comprise a plurality of perimeter discharge openings that define a discharge area. In order to illustrate this principle, FIG. 2 connects perimeter openings 30 via a hypothetical boundary 32, thus depicting the discharge area of discharge device 10. The discharge area shown by hypothetical boundary 32 can have the same dimensions discussed above with reference to the discharge area described with reference to FIG. 1.

FIG. 3 depicts a top view of discharge device 10, and illustrates fluid receiving conduit 36, coupled in fluid communication with feeding conduit 28. In one or more embodiments, fluid receiving conduit 36 can be configured to be rigidly coupled to a sidewall of a water-containing vessel, such as, for example, a pool or spa. Additionally, as discussed in greater detail below, fluid receiving conduit 36 can be configured to receive water from a pump and relay such water to feeding conduit 28.

Fluid receiving conduit 36 can have any shape known in the art that enables its above-described function. In one or more embodiments, fluid receiving conduit 36 can be substantially cylindrical. Additionally, fluid receiving conduit 36 can have a diameter of at least 0.5 inches, at least 1 inch, or at least 1.5 inches. Additionally, fluid receiving conduit 36 can have a diameter in the range of from about 0.5 to about 10 inches, in the range of from about 1 to about 5 inches, or in the range of from 1.5 to 2.5 inches. Furthermore, fluid receiving conduit 36 can have a length in the range of from about 1 to about 20 inches, in the range of from about 2 to about 15 inches, or in the range of from 3 to 10 inches.

Referring now to FIG. 5, an alternate discharge device 110 is depicted comprising a fluid receiving conduit 136, two feeding conduits 128 a,b, four fluid discharge conduits 126 each comprising a plurality of fluid discharge openings 124. Additionally, discharge device 110 comprises a cross-member 138 that can be rigidly coupled to and in fluid communication with fluid receiving conduit 136 and feeding conduits 128 a,b, Cross-member 138 can be configured to direct fluid received via fluid receiving conduit 136 to each of feeding conduits 128 a,b. FIG. 5 additionally depicts a hypothetical boundary 132 connecting each of perimeter discharge openings 130, thus defining the discharge area of discharge device 110.

Fluid receiving conduit 136, feeding conduits 128 a,b, discharge conduits 126, and fluid discharge openings 124 can all have the same dimensions and configurations as fluid receiving conduit 36, feeding conduit 28, discharge conduits 26, and fluid discharge openings 24, described above with reference to FIGS. 1-4, respectively. Additionally, the discharge area of discharge device 110 can have the same dimensions as the discharge area described above with reference to FIG. 1.

Cross-member 138 can be substantially cylindrical and can have a diameter of at least 0.5 inches, at least 1 inch, or at least 1.5 inches. Additionally, cross-member 138 can have a diameter in the range of from about 0.5 to about 10 inches, in the range of from about 1 to about 5 inches, or in the range of from 1.5 to 2.5 inches. Cross-member 138 can have a length of at least 5, at least 7, or at least 10 inches. In one or more embodiments, cross-member 138 can have a length in the range of from about 5 to about 50 inches, in the range of from about 7 to about 40 inches, or in the range of from about 10 to about 30 inches.

Though not depicted, each of cross-member 138 and feeding conduits 128 a,b can optionally comprise a plurality of the above-described fluid discharge openings. In one or more embodiments, cross-member 138 and feeding conduits 128 a,b can individually comprise at least 3, at least 5, or at least 7 fluid discharge openings. In other embodiments, cross-member 138 and feeding conduits 128 a,b can individually comprise a number of fluid discharge openings in the range of from about 3 to about 50, in the range of from about 5 to about 35, or in the range of from 7 to 20.

Referring now to FIG. 6, an alternate discharge device 210 is depicted comprising a feeding conduit 228 and six radially-coupled fluid discharge conduits 226 each comprising a plurality of fluid discharge openings 224. FIG. 6 additionally depicts a hypothetical boundary 232 connecting each of perimeter discharge openings 230, thus defining the discharge area of discharge device 210. Feeding conduit 228, discharge conduits 226, and fluid discharge openings 224 can all have the same dimensions and configurations as feeding conduit 28, discharge conduits 26, and fluid discharge openings 24, described above with reference to FIGS. 1-4, respectively. Additionally, the discharge area of discharge device 210 can have the same dimensions as the discharge area described above with reference to FIG. 1.

As shown in FIG. 6, fluid discharge conduits 226 can be positioned such that adjacent fluid discharge conduits 226 extend outwardly from feeding conduit 228 at a diverging angle. In one or more embodiments, adjacent ones of fluid discharge conduits 226 can diverge outwardly from feeding conduit 228 at an angle of at least 5°, at least 10°, or at least 15°. Additionally, adjacent ones of fluid discharge conduits 226 can diverge outwardly from feeding conduit 228 at an angle in the range of from about 5 to about 179°, in the range of from about 10 to about 150°, or in the range of from 15 to 120°.

Referring now to FIG. 7, an alternate discharge device 310 is depicted comprising a fluid discharge disk 312 in lieu of fluid discharge conduits, as described above. Additionally, discharge device 310 comprises a plurality of fluid discharge openings 324. FIG. 7 also depicts a hypothetical boundary 332 connecting each of perimeter discharge openings 330, thus defining the discharge area of discharge device 310.

Fluid discharge disk 312 can comprise at least 20, at least 30, at least 40, or at least 50 of fluid discharge openings 324. In one or more embodiments, fluid discharge disk 312 can comprise a number of fluid discharge openings 324 in the range of from about 20 to about 500, in the range of from about 30 to about 350, or in the range of from 50 to 200. Fluid discharge openings 324 can have the same dimensions and configurations as fluid discharge openings 24, described above with reference to FIGS. 1-4. Additionally, the discharge area of discharge device 310 can have the same dimensions as the discharge area described above with reference to FIG. 1.

Referring now to FIG. 8, an alternate discharge device 410 is depicted comprising a fluid discharge sidewall 412 in lieu of fluid discharge conduits, as described above. Additionally, discharge device 410 comprises a plurality of fluid discharge openings 424. FIG. 8 also depicts a hypothetical boundary 432 connecting each of perimeter discharge openings 430, thus defining the discharge area of discharge device 410.

In one or more embodiments, fluid discharge sidewall 412 can be formed of at least one structural sidewall of a fluid-containing vessel 414. Fluid discharge sidewall 412 can comprise at least 20, at least 30, at least 40, or at least 50 of fluid discharge openings 424. In one or more embodiments, fluid discharge sidewall 412 can comprise a number of fluid discharge openings 424 in the range of from about 20 to about 500, in the range of from about 30 to about 350, or in the range of from 50 to 200. Fluid discharge openings 424 can have the same dimensions and configurations as fluid discharge openings 24, described above with reference to FIGS. 1-4. Additionally, the discharge area of discharge device 410 can have the same dimensions as the discharge area described above with reference to FIG. 1.

Referring again to FIG. 1, as mentioned above, discharge device 10 can be employed in water-containing vessel 18 as part of current generating device 12. In one or more embodiments, discharge device 10 can be positioned such that the upper edge of feeding member 28 is within 20 inches, 10 inches, or 5 inches of the top of water 22. Additionally, discharge device 10 can be placed a horizontal distance away from wall 40. In one or more embodiments, the rear-most edge of discharge device 10 can be horizontally spaced from wall 40 at least 1, at least 2, or at least 3 inches. In other embodiments, the rear-most edge of discharge device 10 can be horizontally spaced from wall 40 in the range of from about 1 to about 20 inches, in the range of from about 2 to about 15 inches, or in the range of from 3 to 10 inches. Though not wishing to be bound by theory, it is believed that spacing discharge device 10 a horizontal distance away from wall 40 has a multiplying effect on the flow of water from discharge device 10, again possibly explained by Bernoulli's principle. Accordingly, a stronger, smoother current can be generated using less power to operate an attached propulsion device, such as pump 16.

As mentioned above, a portion of water 22 can be withdrawn from fluid inlet 14 and via pump 16, which can then be routed to fluid receiving conduit 36. Fluid inlet 14 is depicted as located in close proximity to pump 16 for illustration purposes only. The location of fluid inlet 14 is not critical, and can be positioned at any ordinarily submerged location in water-containing vessel 18. For example, fluid inlet 14 can be located at the opposing end of water-containing vessel 18 from pump 16. Indeed, such location may actually be more efficient, given that water 22 can be flowing toward the rear of water-containing vessel 18 due to the current generated via discharge device 10. Additionally, any type of plumbing known in the art can be used to fluid connect fluid inlet 14 to pump 16, and pump 16 to fluid receiving conduit 36, including, but not limited to, copper, brass, or plastic tubing.

Pump 16 can be any propulsion device known in the art configured to receive and discharge a volume of fluid. In operation, pump 16 can have a flow rate of at least 20 gallons per minute (“gpm”) at a pressure ranging from about 10 to about 30 pounds per square inch (“psi”). Additionally, pump 16 can have a flow rate in the range of from about 50 to about 400 gpm at a pressure in the range of from about 10 to about 30 psi. In one or more embodiments, pump 16 can have a flow rate of up to 1,000 gpm at a pressure in the range of from about 10 to about 30 psi. Accordingly, the above-described fluid discharge openings can have an average flow rate of at least 0.05 gpm, in the range of from about 0.1 to about 20 gpm, or up to 50 gpm, at a pressure in the range of from about 10 to about 30 psi. In one or more embodiments, pump 16 can have in the range of from about 1 to about 5 horsepower. Furthermore, it should be noted that pump 16 can include a plurality of pumps employed in combination to achieve a desired flow rate. In one or more embodiments, pump 16 can comprise any commercially available pool or spa pumps, such as those produced by Waterway Plastics (Oxnard, Calif., USA).

Water-containing vessel 18 can be any type of water-containing vessel known in the art. In one or more embodiments, water-containing vessel 18 can be large enough to allow an average-sized human adult to swim therein, as depicted in FIG. 1. In one or more embodiments, water-containing vessel 18 can have an average length of at least 10 feet, at least 12 feet, or at least 14 feet. Moreover, water-containing vessel 18 can have an average length in the range of from about 10 to about 200 feet, in the range of from about 12 to about 175 feet, or in the range of from 14 to 150 feet. Additionally, water-containing vessel 18 can have an average width of at least 5 feet, at least 7 feet, or at least 9 feet. Also, water-containing vessel 18 can have an average width in the range of from about 5 to about 125 feet, in the range of from about 7 to about 100 feet, or in the range of from 9 to 75 feet. Furthermore, water-containing vessel 18 can have an average depth of at least 2.5 feet, at least 3 feet, or at least 4 feet. Additionally, water-containing vessel 18 can have an average depth in the range of from about 2.5 to about 20 feet, in the range of from about 3 to about 15 feet, or in the range of from 4 to 10 feet. Water-containing vessel 18 can have any shape known in the art. In one or more embodiments, the surface level of water-containing vessel 18 can be substantially rectangular. In other embodiments, the surface level of water-containing vessel 18 can be substantially circular. In one or more embodiments, water-containing vessel 18 can be a pool, including in-ground or above-ground pools. In other embodiments, water-containing vessel 18 can be a spa.

In one or more embodiments, current-generating device 12 can be integrated during construction of water-containing vessel 18. In other embodiments, water-containing vessel 18 can be an existing structure retrofitted with current-generating device 12. Retrofitting water-containing vessel 18 with current-generating device 12 can comprise the steps of (a) forming at least one water inlet 14 in water-containing vessel 18; (b) fluidly connecting the formed water inlet 14 to a pump 16; (c) fluidly connecting pump 16 to a discharge device 10; and (d) affixing discharge device 10 to a sidewall of water-containing vessel 18. In still other embodiments, discharge device 10 can simply be fluidly coupled to a preexisting propulsion source in water-containing vessel 18. Though not depicted in FIG. 1, pump 16 can be connected to at least one power source in order to operate pump 16. Following installation and placement of water in water-containing vessel 18, the current generated by current-generating device 12 can be employed during swim-in-place exercise.

The preferred forms of the invention described above are to be used as illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments and modes of operation, as set forth herein, could be readily made by those skilled in the art without departing from the spirit of the present invention.

The inventor hereby states his intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of the present invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set forth in the following claims. 

1. An apparatus for creating a current in a water-containing vessel for use during swim-in-place exercise, said apparatus comprising: at least one discharge device configured to receive water from said water-containing vessel and to discharge at least a portion of said water back into said water-containing vessel, said discharge device comprising at least 20 spaced-apart, fluid discharge openings, wherein said fluid discharge openings include a plurality of perimeter discharge openings, wherein the area defined by said perimeter discharge openings is in the range of from about 0.5 to about 20 square feet.
 2. The apparatus of claim 1, further comprising at least one pump and at least one fluid inlet configured to receive water from said water-containing vessel and route at least a portion of said water to said pump, wherein said discharge device is configured to receive water from said pump and to discharge at least a portion of said water into said water-containing vessel.
 3. The apparatus of claim 1, further comprising at least 3 fluid discharge conduits each comprising a plurality of said fluid discharge openings.
 4. The apparatus of claim 3, wherein said fluid discharge conduits are arranged in a substantially horizontal manner, substantially parallel to one another, wherein said fluid discharge conduits are substantially cylindrical in shape.
 5. The apparatus of claim 3, wherein said fluid discharge conduits are arranged in an alternating staggered fashion such that adjacent ones of said fluid discharge conduits lie in different vertical planes.
 6. The apparatus of claim 3, wherein adjacent ones of said fluid discharge conduits are vertically spaced apart at least 0.5 inches on center, wherein said fluid discharge conduits have individual lengths in the range of from 5 to 50 inches.
 7. The apparatus of claim 3, further comprising at least one feeding conduit in fluid communication with all of said fluid discharge conduits, wherein said feeding conduit is positioned substantially perpendicular to said fluid discharge conduits.
 8. The apparatus of claim 3, wherein each of said discharge conduits comprises at least 5 of said fluid discharge openings.
 9. The apparatus of claim 1, wherein said fluid discharge openings are substantially circular in shape, wherein said fluid discharge openings each have individual diameters in the range of from about 1/32 to about ⅜ of an inch, wherein the average spacing between adjacent ones of said fluid discharge openings is at least ⅛ of an inch.
 10. The apparatus of claim 1, wherein the area defined by said perimeter discharge openings has a maximum width in the range of from about 10 to about 60 inches.
 11. The apparatus of claim 1, wherein the area defined by said perimeter discharge openings has a maximum height in the range of from about 4 to about 50 inches.
 12. The apparatus of claim 1, wherein the area defined by said perimeter discharge openings is in the range of from about 0.75 to about 10 square feet.
 13. The apparatus of claim 1, wherein all of said fluid discharge openings are configured to discharge a liquid in substantially the same direction, wherein said apparatus comprises at least 40 of said fluid discharge openings.
 14. An apparatus for creating a current in a water-containing vessel for use during swim-in-place exercise, said apparatus comprising: (a) at least one pump; (b) at least one fluid inlet configured to receive water from said water-containing vessel and route at least a portion of said water to said pump; and (c) at least one discharge device configured to receive water from said pump and discharge at least a portion of said water into said water-containing vessel, said discharge device comprising at least 3 distinct fluid discharge conduits each comprising a plurality of spaced-apart, fluid discharge openings, wherein said discharge device comprises at least one feeding conduit in fluid communication with all of said fluid discharge conduits and said pump, wherein said discharge device comprises at least 30 of said fluid discharge openings.
 15. The apparatus of claim 14, wherein said fluid discharge conduits are arranged in a substantially horizontal manner, substantially parallel to one another, wherein said fluid discharge conduits are substantially cylindrical in shape.
 16. The apparatus of claim 14, wherein said fluid discharge conduits are arranged in an alternating staggered fashion such that adjacent ones of said fluid discharge conduits lie in different vertical planes.
 17. The apparatus of claim 14, wherein adjacent ones of said fluid discharge conduits are vertically spaced apart at least 0.5 inches on center, wherein said fluid discharge conduits have individual lengths in the range of from 5 to 50 inches.
 18. The apparatus of claim 14, wherein said discharge device comprises at least 40 of said fluid discharge openings, wherein said fluid discharge openings comprise a plurality of perimeter discharge openings, wherein the area defined by said perimeter discharge openings is in the range of from about 0.5 to about 20 square feet.
 19. The apparatus of claim 18, wherein the area defined by said perimeter discharge openings has a maximum width in the range of from about 10 to about 60 inches and a maximum height in the range of from about 4 to about 50 inches.
 20. The apparatus of claim 14, wherein said fluid discharge openings are substantially circular in shape, wherein said fluid discharge openings each have individual diameters in the range of from about 1/32 to about ⅜ of an inch, wherein the average spacing between adjacent ones of said fluid discharge openings is at least ⅛ of an inch.
 21. A method for generating a current in a swim-in-place vessel, said method comprising: circulating water contained in said vessel through a current-generating device comprising at least 20 spaced-apart, fluid discharge openings having an average diameter of less than ⅜ of an inch.
 22. The method of claim 21, wherein the total flow rate of said water through said current-generating device is in the range of from about 50 to about 400 gallons per minute (“gpm”), wherein the average flow rate of said water through each of said fluid-discharge openings is in the range of from about 0.1 to about 20 gpm.
 23. The method of claim 21, wherein said current generating device comprises: (a) at least one pump; (b) at least one fluid inlet configured to receive at least a portion of said water from said vessel and route at least a portion of said water to said pump; and (c) at least one discharge device configured to receive water from said pump and discharge at least a portion of said water into said vessel, said discharge device comprising at least 3 distinct fluid discharge conduits each comprising a plurality of said fluid discharge openings.
 24. The method of claim 21, wherein said fluid discharge openings comprise a plurality of perimeter discharge openings, wherein the area defined by said perimeter discharge openings is in the range of from about 0.75 to about 10 square feet.
 25. The method of claim 24, wherein the area defined by said perimeter discharge openings has a maximum width in the range of from about 10 to about 60 inches and a maximum height in the range of from about 4 to about 50 inches.
 26. The method of claim 21, wherein said vessel comprises a pool or a spa, said method further comprising retrofitting said pool or spa with said current-generating device. 